Print & Ink Cost Calculations

Print Cost & Ink Yield Calculations
The Cost of the Ink you buy

Ever wondered what the cost is of printing your own stuff or the cost of the ink?

Depending on what quality we choose, we know print cost of given print size when we get our image's) back from the color lab. Making your own prints however, this information appears to get lost in the shuffle so, I decided to try to calculate the cost of one square inch of printed matter on a good piece of printing stock using an Epson 2200 I currently use. This printer has seven ink cartridges.

Known data,

Epson 2200 Stylus Printer Cartridge @ average cost of $ 11.35
Epson 4 x 6 Glossy paper 100 pack @ $ 13.50.
Epson Premium Luster paper 50 pack @ $ 115.00.
Ink Cartridge life according Epson (Black or Colored) 440 Print area pages (8.5x11) @ 5% coverage @ 360 DPI. (2057 inch sq.) (info. obtained from Epson Tech. Dept)

Calculated data,

Cost of one square inch of 4 x 6 Epson Glossy paper = (13.50 / 100) / (4x6) = $ 0.005517
Cost of one square inch of Epson Premium Luster paper = (115 / 50) / (13x19) = $ 0.0093.
Page yields @ 1440 DPI @ 5% = 440 / (1440/360) = 110 pages @ 5%
Page yield @ 100% coverage is 110 pages / (100% / 5%) = 5.5 pages.
One 8.5 x 11 page is 93.5 inch/sq. minus unprintable area (margins) = 76.875 inch/sq. printable area.
Total ink cartridge yield is page square inches x page yield @ 100% = 76.875 inch/sq. x 5.5 pages = 422.81 square inches*
Cost of one square inch of ink is Cartridge cost / cartridge yield = $ 11.35 / 422.81 = $ 0.0268

Cost of one square inch of printed image on Epson 4 x 6 Glossy stock is Cost of Epson 4 x 6 Glossy paper + cost of ink = $0.0056 + $0.0268 = $0.0324

Cost of one square inch of printed image on Epson Premium Luster stock is Cost of Epson Luster paper + cost of ink = $0.0093 + $0.0268 = $ 0.0361

Average print cost and cartridge yields per print size,*
Cost below, does not include cost of image processing and equipment depreciation.

Size		Cost	Av/Yld/Cart	Av/yld/7cart	Average commercial cost
4 x6	24 x 0.0324=	$0.77	21	150	$0.25 to $0.32 at local 1 hour
5 x 7	35 x 0.0361=	$1.26	14	100	$0.26 to $0.52 at local 1 hour
8 x 10	80 x 0.0361=	$2.88	6.5	48	$1.30 to $4.80
12 x 18	216 x 0.0361=	$7.79	2.4	17	$11.00 to $17.00 custom color lab.
13 x 19	247 x 0.0361=	$8.91	2	14	$13.00 to $20.00 custom color lab.

The Cost of the Ink you buy
Have you ever wondered about the cost of the ink when you purchase a cartridge for your printer? Everyone has. When you have to pay $28.95 for an ink cartridge replacement you can not help but wonder why so much!

Actually, the ink at cartridge retail is far more then most of us can comprehend. Far more then most liquids we know of. Most cartridges hover around 1.5 ML to 2.25 ML. For this example lets use a 2 ML cartridge at a cost of $28.95. Lets calculate the hypothetical cost per gallon.

One Liter contains 1000 ML thus, we get 500 - 2 ML cartridges from a Liter. Therefore, a Liter would retail at 500 x $28.95 = $14,475.00.
There are 3.785 Liters in a Gallon so, $14,475.00 x 3.785 = $54,787.87
That is a lot of money. This astonishing figure is probable not realistic because there is, after all, the packaging however, it demonstrates that the ink business is a worthwhile business deserving all the warning labels we find on our printer not to substitute the ink. The question why the high prices? To the best of my knowledge there is no answer for this and no articles written or outcries from user groups other then it appears to support the inkjet printer marketing effort. You want a cheap printer, then pay for the ink.